[ih] Autodin II

[Dave Crocker]

As the auth-results header field shows, the specific issue is their 
publishing a DMARC record directing the receiving host to reject mail 
that does not validate DKIM (using the author From field domain) or SPF. 
  Their use of DMARC this was set new precedent and it is indeed mailing 
list unfriendly.  There currently is no fix for it from the DMARC publisher.

The only hack that seems to work is modifying the author From: field 
address to use a different domain.  This often conforms to a template 
such as:

    From:  Original Display Name via listname
           <listname at listhost.example.>

or the like.

The premise that this somehow provides generally-useful anti-abuse 
protection is, shall we say, controversial.  However it does preclude 
unauthorized third-party's use of the originating host's domain name in 
the From: field...

d/

On 1/22/2017 12:39 PM, Eitan Adler wrote:
> On 22 January 2017 at 09:50, Alex McKenzie <amckenzie3 at yahoo.com> wrote:
>> Friends,
>>
>> For some reason my responses to postings in Internet History seem to be
>> falling into a black hole.
>
> This might be cause yahoo.com is mailing list hostile in that it does
> not allow non-yahoo addresses to send mail on your behalf. This
> results in emails failing DMARC tests.
>
> Authentication-Results: mx.google.com;
>        dkim=neutral (body hash did not verify) header.i=@yahoo.com;
>        spf=neutral (google.com: 128.9.160.161 is neither permitted nor
> denied by best guess record for domain of
> internet-history-bounces at postel.org)
> smtp.mailfrom=internet-history-bounces at postel.org;
>        dmarc=fail (p=REJECT sp=REJECT dis=NONE) header.from=yahoo.com
>
>
>


-- 

   Dave Crocker
   Brandenburg InternetWorking
   bbiw.net